2nd derivative, is my answer correct

  • Thread starter Thread starter neutron star
  • Start date Start date
  • Tags Tags
    Derivative
Click For Summary

Homework Help Overview

The problem involves finding the velocity and acceleration of a particle moving along the x-axis, given its position function s(t) = 7t² + 33. The original poster expresses uncertainty about the correctness of their derivatives and whether the variable should be 'x' or 't'.

Discussion Character

  • Conceptual clarification, Mathematical reasoning

Approaches and Questions Raised

  • The original poster attempts to differentiate the position function to find velocity and acceleration, initially confusing the variable 't' with 'x'. Other participants clarify the correct use of 't' and confirm the derivatives.

Discussion Status

Participants are engaged in clarifying the differentiation process and correcting variable usage. Some have confirmed the derivatives as correct, while others inquire about the method used to obtain them, specifically referencing difference quotients.

Contextual Notes

There is a mention of confusion due to working on multiple problems with different variables, which may have influenced the original poster's notation.

neutron star
Messages
78
Reaction score
1

Homework Statement


The position of a particle moving along the x-axis is given by s(t)=7t^2+33. Use difference quotients to find the velocity v(t) and acceleration a(t).

My textbook says v(t)=s'(t) and a(t)=s''(t). I think I got the answer, but not sure if the velocity should have an x in it. Please reply and let me know.

Homework Equations





The Attempt at a Solution


s(t)=7t^2+33
s'(t)=14x
s''(t)=14
 
Physics news on Phys.org
Where did the x come from?
s(t) = 7t^2 + 33
so by using the power rule s'(t) = 7*2(t(2-1)) = 14t
 
Sorry I meant t. I was doing a bunch of problems, mostly with x so I got mixed up when I was typing. I meant:

s(t)=7t^2+33
s'(t)=14t
s''(t)=14
 
[PLAIN]http://calc101.com/Calc101/MSP?MSPStoreID=MSPStore10452429_0&MSPStoreType=image/gif

Yes, you are correct.
 
Last edited by a moderator:
neutron star said:
Sorry I meant t. I was doing a bunch of problems, mostly with x so I got mixed up when I was typing. I meant:

s(t)=7t^2+33
s'(t)=14t
s''(t)=14
These are correct. Did you get s'(t) and s''(t) using difference quotients?
 

Similar threads

Replies
7
Views
2K
Replies
8
Views
1K
Replies
4
Views
2K
  • · Replies 8 ·
Replies
8
Views
3K
  • · Replies 4 ·
Replies
4
Views
2K
  • · Replies 17 ·
Replies
17
Views
2K
  • · Replies 10 ·
Replies
10
Views
5K
  • · Replies 2 ·
Replies
2
Views
2K
  • · Replies 5 ·
Replies
5
Views
2K
  • · Replies 1 ·
Replies
1
Views
2K